Rolf Dekker stared incredulously at the slim, handsome young Earther who was approaching the steps of Rolf's tumbling-down Spacertown shack. He's got no ears , Rolf noted in unbelief. After five years in space, Rolf had come home to a strangely-altered world, and he found it hard to accept. Another Earther appeared. This one was about the same size, and gave the same impression of fragility. This one had ears, all right—and a pair of gleaming, two-inch horns on his forehead as well. I'll be eter